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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

New to Valve Amps and Confused???

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Low power SE to Higher power Push Pull, from pentode to triode??? I have recently built some bass reflex speakers about the size of medium sized fridges with 12" audio nirvana full-range speakers. They are very efficient speakers, rated at 96db but in the cabinet about 99db. I listen to music ranging from acoustic to rock. Now I am interested in moving my transistor power amp on and getting a valve amp. Is it best to go integrated or a power amp, and if a power amp am I best to get mono blocks or is it not that important due that my speakers need hardly anything to power them??and what style of valve amp that will not only suit jazz and classical but also rock? And what size valves 300b's,KT88's ect I am finding this whole valve amp world very overwhelming ?? Can some one help me please :confused:
 
The separates/integrated question is a personal one, and it depends on your situation. Personally, I like the flexibility separates can offer - you can swap out preamps and PAs to your heart's content until you find a combo that you really like. But at the same time, I recently moved my setup back from my apartment at college, so I know how much of a pain in the *** it is to move all that stuff ;)

Those Audio Nirvanas are rated for 30W, right? You could run the higher-powered PP amps (EL34s, KT88s) but you'd have to stay easy on the volume control, or else you'll be smelling coil. My Fostex Sigs are similar in sensitivity, and the 8 watts from my SV811 monos are enough to get some good volume out of them, and I do break out the headbanging material :) 300Bs in SET would be similar in power.

Push/pull EL84s would be another option for more power, but not enough that you'd have to worry about smoking the drivers as long as you stayed unclipped.
 
Welcome!

Paul:
First off congrats on you " refrigerator" build...the guys at the Full-range forum would really like to see em' as I would.PIX??
Lets see if I could offer up some observations.
As to the integrated or not....most all tube amps are straight amp with no controls, with a simple input level control. Why? Most feel the pre-amp section should be seperate as engineering a pre-amp has its' own oddities that are best contained within its own chassis.
Mono-blocks are of an esthetically different beast..can be broken up in your system "rack" in all different locations. My guess is that mono-blocks were originally thought up because of tight space confines trying to fit everything into a single chassis.
As to Single-ended vs. Push-pull...First if we assume you will be expecting to get an SPL of the "required" 115 DB to get to maximum volume "Rock Concert" levels we are looking at 32 Watts per channel. Again your full-rangers will more than likely not get to these levels.
Look up the rating for your 12" drivers....& ask yourself if you think you would dare to drive them that loud.
IMHO I prefer single-ended...The guys that stitch their signal together just doesn't do it for me.
I like the minimalistic approach. "A Few Good Tubes".They can be big! but few.
Will you be building your own or buying a kit or a pre-built?
2A3, 300B, KT88,845,813......All can be set-up as a two to three stage SE from Four to Fourty-Five Watts.
The Full on rock music levels will be determined more on your loudspeakers than the amp driving them.
PIX, Pix, pix.
_______________________________________________________Rick...
 
I have recently built some bass reflex speakers about the size of medium sized fridges with 12" audio nirvana full-range speakers. They are very efficient speakers, rated at 96db but in the cabinet about 99db.

Speaker efficiency is a very important fact. Paul Joppa has provided us with a very useful rule of thumb. Joppa's Rule states that in a "typical" listening space an amp/speaker combo should be capable of reaching 102 dB. SPL peaks at a 1 M. distance. A truly small space will need less power, while a room with a cathedral ceiling or "head banger" Rock will need more.

You are probably OK with 2A3 based SE amplification, but the cost will be substantial. May I immodestly suggest "El Cheapo"? The 6 WPC a triode wired "El Cheapo" yields will certainly be sufficient, at a very nice price. The SAGA of "El Cheapo" is here.
 
Another good option, RH84:
http://www.tubeaudio.8m.com/RH84/rh84_sch.gif
There is also a big brother to this amp, the RH807. It is also fairly easy to build and gives you about double the output power:
http://www.tubeaudio.8m.com/807/se807_sch_2.gif
If you didn't mind spending a bit more money (slightly more costly tubes than El Cheapo) you could do something like the AudioTropic Musical Machine:
http://www.audiotropic.net/Projects/implement.html
The beauty is that it is such a simple amp that it isn't to expensive to "lux out" on this one. It is very related to the El Cheapo above.
If you really had time and/or money to spend you could look to SE 45, 2A3, or 300B:
http://www.positive-feedback.com/Issue1/single.htm
http://www.the-planet.org/images/2A3--6SL7_small.jpg
http://www.electra-print.com/300bdrd.php
These are some of my favorites of each, though they are all DC coupled which can be a whole other can or worms for a first time builder.
I cannot end without mentioning the amps I think I should have mentioned first, the Tubelab Simple SE and Tubelab SE:
http://www.tubelab.com/
They are very popular builds and there is tons of information that can be found around here. Plus if you get stuck bad, the designer is a (great) active member of this forum. The other nice thing with these is that they are PCB's, easy to build and relatively safe to poke around in....relatively. $78 can get you one of each PCB so you could start with an inexpensive Simple SE build, tweak it, and when you wanted to hear something else, build up the Tubelab SE with your choice of DHT.
Of course the designers and/or builders of all of the above amps are around, very nice, and willing to help. I have had a couple of conversations with Jack at Electra-Print (the 300B design), and he is a great guy.

Restating what was said above, read up on tube safety if you are going to build. The voltages here will scare and hurt like hell at the very very best. These voltages can kill you very dead if you are foolish. However, don't let that discourage you, just read up on proper safety and be very careful, especially at first. Eventually you will get more relaxed around these things, but don't get to relaxed, it can lead to carelessness. I know the first time I poked around inside a couple of my amps I was terrified, but it eased over time. Now I would say I am comfortable but vigilant, or something like that.

Cheers and happy listening!

James
 
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Speaker Photo's

Thanks to all who have given there help and advice. I was going to buy a already built amp but now i am considering building my own from a kit. I think I might go with a SET amp.I am looking at spending about AUD$1500. So am i best to go a power amp rather then a intergrated amp? Here are some photo's of my speakers. 115cm h 48cm w 38cm d 6"port 12kg granite tops, they weigh nearly 50kg each including the stone tops. The drivers are Fullrange Caste frame 12" audio nirvana's. My CD player (CD8x),pre amp(aCA7.5Pre) and power amp(Q power) are all Cyrus, an English brand. I have a mate who's parent in laws import the stuff into Australia. I bought it without to much thought but now am looking for truth in my sound. The speakers were built about a month ago and they are amazing but i do believe they could sound so much better with the right gear behind them. Thanks again.
 
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